Stop in Carshalton (4)
I believe the answer is:
halt
'stop' is the definition.
(halt can mean to stop)
'in carshalton' is the wordplay.
'in' says the answer is hidden in the clue.
'HALT' is hidden in the letters of 'carshalton'.
(Other definitions for halt that I've seen before include "Pull up" , "game" , "Small railway station" , "Falter - stop" , "Stop or pause" .)